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Paint Calculator
Estimate how many gallons of paint you need for a room.
Paint Calculator
Legendary surface mapping with coat-perfect precision.
Wall Dimensions
Deductions & Options
TOTAL VOLUME REQUIRED
0
Gallons
Total Surface Area
0 sq ft
Estimated Cans (1 Gal)
0
Volume in Liters
0 L
Note: This estimate assumes standard wall surfaces. Rough or porous surfaces may require up to 20% more paint.
About the Paint Calculator
Estimate how many gallons of paint you need for a room.
How to use the Paint Calculator
- Enter the Wall Length (ft), Wall Height (ft) and No. of Walls.
- Enter the number of Windows / Doors, the Coats of Paint and the Coverage (sq ft/gal) from the tin.
- Press Estimate Volume.
Formula and method
Gallons = (wall area − windows and doors) × coats ÷ coverage per gallon. One gallon covers about 350 sq ft.
When to use the Paint Calculator
- Working out how many litres or gallons of paint a room needs.
- Budgeting a decorating job.
- Avoiding wasted paint and second trips to the shop.
Common mistakes to avoid
- Forgetting the ceiling and the trim.
- Ignoring that dark colours and rough walls need extra coats or a primer.
Tips
- Rough or dark walls may need extra paint or a primer.
- Buy a little extra for touch-ups.
Frequently asked questions
How much area does one gallon cover?
About 350 sq ft for one coat on a smooth wall.
How many coats do I need?
Two coats is standard. A dramatic colour change may need three, or a primer first.